Israel didn't lose the war in Lebanon on the day of the invasion, nor the day it left Lebanon on May 25, 2000. But in early September, 1982, there was a moment, only a week-and-a-half long, when the entire adventure hung in the balance between success and failure. It began with Yasser Arafat and the PLO leaving Beirut and ended with the assassination of the elected president, Bashir Gemayel. During that brief moment, President Reagan announced his peace plan for the Israeli-Arab conflict and Gemayel made clear to then-premier Menachem Begin that as the newly elected president of Lebanon, he would not fulfill Begin's wishes. The government should have pulled itself together then, and immediately brought the IDF home. If it had done so, there never would have been Israeli involvement in the Phalangist massacre in Sabra and Chatila, the war's failure would not have been so great, and the political careers of Begin and his defense minister, Ariel Sharon, would not have crashed - finally for Begin, and in Sharon's case, for 18 years.

Sharon should have learned that lesson, but his biography, both military and political, is rife with bad timing. So it is only to be expected that he'll miss the opportunity now, after the bombings in Jerusalem and Haifa.

The war on terror needs an integrated, three-pronged approach: defensive, offensive, and political. Without the consent of the superpower, Israel's offensive means are limited, so it must rely on defensive action. And no matter how sophisticated the defenses become, they will never be perfect. One attack can be foiled, and so can another and even hundreds, but prevention alone won't dry up the phenomenon of terrorism.

The best defense isn't at the last line of defense, which once breached, means the terrorist can reach the target. Major General Yitzhak Eitan has had almost seven years of experience dealing with post-Oslo terrorism (two years as Gaza corps commander, three as West Bank corps commander, and now, for the last 18 months, head of Central Command). He regards the sieges and closures of West Bank towns, where the terrorists come from, as a bad but necessary obstacle, needed to prevent the cells and their munitions from reaching Israel. It's bad because it disrupts civilian life and increases hostility, but necessary, because it gives the preventive forces - security services, army, and police - the day, hours, and sometimes minutes that make the difference between a bomb that goes off and one that doesn't.

Eitan believes that the most important framework for the fighting forces in the territories is the regional brigade, which specializes in the area where it is posted. The brigades should therefore be strengthened with forces and officers, instead of wasting hundreds of jobs on dividing the West Bank corps into two, as proposed by Major General Shai Avital. It is possible that the borders of the northern brigades - Shomron, Ephraim and Menashe - will be redrawn so that one of them is more or less subsumed by another. Eitan believes the proper deployment is laterally, in the current structure, and not in a long and narrow strip, as the "seam" along the Green Line was organized for a few months until its improvised headquarters was closed down a week ago. With practically no chance of foiling an attack in the area where the attackers are approaching their targets, the "seam" command was not much different from the Jerusalem District Police.

Reinforcement of the defensive systems in the territories, however, is not practical, because it would come at the expense of the northern border, which could burst into flames at the initiative of Hezbollah or as another front in an American (and Israeli) campaign against Iraq. Eitan told the general staff that given the overall needs of the IDF, it would be better not to weaken the northern command in order to strengthen the central one.

Defense is not enough; and an offensive - against Palestinian Authority security services that aren't taking action against the terrorists and sometimes cooperate with it - won't accomplish anything if it's not accompanied by a political plan that would follow the military operation. However, for that kind of statesmanship, combining the desire for peace with the readiness for war, Sharon needs American support. But Sharon is Sharon, and there's reason to be skeptical that he rose to the occasion during his conversation yesterday with President George W. Bush.

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